Method of accurately locating a metal plate upon a stationary article



y 17, 1956 H. M. GASSTROM 2,754,516

METHOD OF ACCURATE LOCAT A METAL PLATE UPON A ST ONARY TICLE Filed Nov. 14, 1951 2 Sheets-Sheet l IN V EN TOR:

HERMAN M.GA55TROM ATTORNEY.

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July 17, 1956 H. M. GASSTROM 2,754,515

- METHOD OF ACCUR LY LOCATING A METAL PLATE UP R AR ON A ATIONA Y TICLE Filed Nov. 14, 1951 2 Sheets-Sheet 2 62 INVENTO HERMAN M GASSTR ATTORNEY.

United States Patent O METHOD OF ACCURATELY LOCATIN G A METAL PLATE UPON A STATIONARY ARTICLE Herman M. Gasstrom, Pelham, N. Y.

Application November 14, 1951, Serial No. 256,342

4 Claims. (Cl. 1--82) This invention relates to methods for accurately guiding hinge plates into position upon the individual legs of folding rules and the like.

The main object of my invention is to provide a method for effecting the accurate positioning of hinge plates upon folding rule members preparatory to clinching the plates in position thereon.

Another object is to provide a method for properly placing and holding the hinge plates against displacement when the same plates are being clinched into permanent association with the. rule members involved.

The overall object of the invention is to ensure the accurate permanent disposition of metal plates upon rule legs which are hinged together in such fashion that these members when folded together will be located accurately in line one above the other.

An ancillary object is to facilitate manufacture of folding rules at high speed without sacrificing quality in the product.

Other objects and the advantages of my invention will appear in further detail as the specification proceeds.

In order to facilitate ready comprehension of this invention for properly appreciating the salient features thereof, the invention is illustrated on the accompanying drawings forming part hereof, and in which:

Figure 1 is a vertical section through a die for cutting.

free a hinge plate and" accurately positioning the same upon a rule leg, the latter being shown in operative position in the die;

Figure 2' is to top or plan view of the same die and the rule leg being shown as extending rearwardly from the die;

Figure 3 is an enlarged fragmentary plan view of the die block which effects the final cutting free of the hinge plate as per Figures 1 and 2;

Figure 4 is a transverse section of the punch of the die block shown in Figures 1 and 3;

Figure 5 is an enlarged plan view of a sheet metal hinge plate of Figures 1 and 2;

Figure 6 is a transverse section through the hinge plateof Figure 5 as taken on line 6-6;

Figure 7 is an enlarged fragmentary section' of the die structure of Figure 2 as taken on line 7-7-;

Figure 8 is a further section of therule leg similar to that shown in Figure 7 but with the side edges of the hinge plate clinched, the section being taken on line 8-8 in Figure 9;

Figure 9 is a plan view on anenlarged scale ofthe rule leg of Figures 7 and 8. showing the'hinge plate fixed in position;

Figure- 10 is an enlarged fragmentary view similar to Figure 3 showing a. modification of the die block of said' Figure 3;

Figure 11 is a transverse section of, a punch fitting the die block of Figure 10;

Figure 12 is another modification of the die block of Figure 3;

Patented July 17, 1956 Figure 14 is a further modification of the die block of Figure 3;

Figure 15 is a transverse section of a punch fitting the die block of Figure 14;

Figure 16 is yet another modification of die block; while Figure 17 is a transverse section of the punch serving to co-operate therewith.

Throughout the views, the same reference numerals indicate the same or like parts.

In folding rules, particularly those in which the individual rule sections or legs swivel at the ends upon the adjacent sections, appearance of the rule when folded is of importance, as the same imparts the impression of accuracy or inaccuracy of the rule as a whole. For example, when the folded sections are askew with respect to each other and do not form a perfectly straight assemblage, with one section slightly off to one side and the next just a little off to the other side, the rule looks irregular and anything but reliable. This is true despite the fact that when this is discounted by salesmen, the rule is also not straight when extended and therefore altered in length and actually inaccurate. Thus, the appearance is an index of the accuracy of the folding rule, not to mention that an irregular folded rule looks old or used and is thus undesirable from every standpoint, including also lack of sales appeal. Upon considering this problem, it has occurred to me that when the rule sections appear relatively askew, this is obviously a matter of slightly inaccurate placing and setting of the hinge plates onthe rule sections during manufacture. In order to remedy this condition, I have designed special dies and hinge plates co-operating with the dies to ensure absolutely accurate location of the plates on each rule section, so that all sections will lie directly over each other when folded and the rule straight when extended.

Hence, in the practice of my invention, and referring again to the drawings, on a press having a die shoe .1 is secured a die block 2 having an upright cavity generally indicated at 3 extending a limited distance down into the die and having a side passage or outlet 4 along the bottom of the cavity, forming a supporting station for a rule section. An extension 6 upon the die block continues the bottom of the cavity as an open upper surface for supporting objects, as will be explained in detail later on.

Upon die block 2 is formed a substantially horizontal feeding passage '7 by a pair of side walls 3 and 9 secured to the die in any desired manner known in the art. These side walls form guides for a spring pad 10 and at least the lower block 11 of a die holder 112, the die holder assembly 11 and 12 serving to support and operate a hinge punch or plunger 13. The latter is held at the upper end by afiange 14 recessed into the lower member 11 of the die holder assembly. Normally, the spring pad It) is spaced at predetermined distance down from the holder member 11 by one or more springs 15 surrounding a guide pin 16 extending slidably through die holder assembly member 12. The spring in each case likewise extends entirely through a clearance bore 17 in holder member 11 and presses directly upon spring pad 10 into which the lower threaded end 18 of guide pin is screwed so that the pin follows the movements of pad Ill. At the upper extremity of the guide pin is an integral head 19 recessed in a short open bore 29 in upper holder member 12, allowing the head to rise in the bore when pad ll) is caused to approach the die holder assembly.

The punch 13 terminates just short of the lower surface of spring pad ltland is provided with a central pilot pin 21 of conical form. The upper surface 22 of die 2 is adapted to support a fiat strip of sheet metal such as brass or steel indicated at 23 between walls 3 and 9 in such fashion that the strip may be fed through passage 7 toward cavity 3. When the press is operated so that die holder assembly 11 and 12 with punch 13 descends, spring pad 10 first engages upon the strip 23 and holds it firm until the punch makes contact with the strip and cuts through and then descends through cavity 3 in die 2.

The metal strip 23 is cut in preliminary fashion as shown at 24 before being cut loose at the ends of each plate section 25 and brought down by the punch upon a rule section or leg 26 extending into the bottom of cavity 3 of the die through a rear passage 27. The pilot pin first engages in center hole 28 and then the punch 13 cuts the plate 25 free at the ends 29, 29 by its cutting ends 30, 30 which co-operate in shearing fashion with the die ends 31, 3.1. The plate is provided with side flanges 32, 32 already formed before the cutting off operation by a previous step which forms no part of the present invention.

As may best be seen in Figures 2, and 6 to 9, not only a center hole 28 and side flanges 32, 32 are previously provided upon the partly cut portion 24 of the metal strip 23, but a group of perforations 33, 33, etc., are punched through the same to form locating points adapted to project into the wood or other body material of the rule section or leg 26. When the metal plate 25 is thus cut free from the strip and pushed down through the die 2 it is forced into intimate contact with rule leg or section 26, thus forcing the projections or points 33 into the leg and setting the plate in desired accurate position. However, in order to ensure such accurate setting of the plate on the rule leg, the plate is cut or profiled in a very special manner and form from the metal strip.

Die 2 in its cavity is formed at the ends 31, 31 with a pair of shoulders 34, 34 with which corresponding shoulders 35, 35 upon punch 13 co-operate to cut guiding shoulders 36, 36 at each end of plate 25, these guiding shoulders when cut by punch 13 slide down along die shoulders 34, 34 and are positively guided during the entire travel of the plate downwards toward the rule leg and until the points 33 are actually embedded in the leg. Thus, the accurate disposition of hinge plate 25 is preserved and directly applied to rule section 26 without any shift of plate 25 being possible in lateral directions from the moment when the plate is cut free and its forcible placing upon the rule leg at the bottom of cavity 3. Of course, with the plate 25 in direct contact with this leg after being pressed thereon by punch 13, no shift laterally with respect to the rule leg will then occur, because the locating points 33 extend into the material of the leg and serve as prongs which occupy seats which they have formed in the leg by pressure of punch 13.

When the plate has thus definitely been placed on the rule section or leg, the latter is passed out upon extension 6 of the die through passage 5, so that this rule leg rests out upon the surface 5 for a side clinching operation partly represented at the right in Figure 1. As the rule leg is passed out from the interior of die 2, the side flanges 32, 32 of plate 25 are yet in preliminary divergent position as best seen in Figures 1, and 5 to 7. Exteriorly of the cutting zone of the die are a pair of clamping members 37, 37 operatively brought together in known manner by means not shown, as such means form no part of the invention as such. The result is that the side flanges are clinched into clamping relation with the rule leg. A presser foot or plunger 33 is preferably brought down upon the plate during this operation to hold the hinge plate in place.

The rule section or leg when thus provided with accurately placed and clinched plates at the ends is then ready for assembling with other rule sections in such manner as to build up a complete folding rule. Due to the method and means already described for ensuring accurate placing of the hinge plates in each case on the rule sections, all of the latter will accurately overlie each other in a straight column in such fashion as to appear clean cut and accurate.

Naturally, certain modifications may be resorted to by altering the guide means used upon the hinge plates, as for example, in Figures 10 and 11 are shown a die 39 with an opening 40 with a punch 41 adapted to co-operate therewith. Die 39 has end cutting portions 42, 42 with which cutting ends 43, 43 of punch 41 cooperate, while the die has end guides or substantially square grooves 44, 44 with which corresponding end ribs 45, 45 on the punch co-operate to form guide projections of substantially square form upon the ends of hinge plates for the rule sections involved.

Then again, as shown in Figures 12 and 13, a die 46 has a punch 47 with which it co-operates, being provided in its cutting ends 48, 48 with guide grooves 49, 49 in each case. The punch upon its ends 50, 50 has two pairs of guide projections 51, 51 fitting the grooves 49, 49 of die 46 and will, of course provide a hinge plate with corresponding guide projections upon the ends thereof.

Also, as shown in Figures 14 and 15, the die 52 is adapted to co-operate with a punch 53 and the cutting ends thereof at 54, 54 co-operate in shearing manner with the ends 55, 55 of the punch. In this case, a single guide projection 56 is formed interiorly on the die at each end 54, while the punch has a corresponding guiding groove 57 at each end 55. The projections 56, 56 and corresponding grooves 57, 57 cut single guide notches in the ends of binge plates in obvious manner.

In Figures 16 and 17 a die is adapted to have a punch 59 co-operate therewith and upon its cutting ends 60, 60 is provided with inwardly projecting guide ribs of substantially rectangular form at 61, 61 fitting corresponding grooves 62, 62 in the ends 63, 63 of punch 39 and forming corresponding rectangular notches in the ends of the hinge plates which are out free from the flat stock or the like by this die and punch couple.

The hinge plates cut free and profiled at the ends thereof by these modifications of die 2 and punch 13 are superfluous to show, as they must resemble hinge plate 25, except for the profiled guide means cut at the ends of the plate by the dies and punches of Figures 10 to 17 inclusive in obvious manner. In each case, the purpose and result are the same, namely, to so form and guide a hinge plate into accurately placed position upon a rule section preparatory to permanently securing the hinge plate thereon, so that when the flanges of the hinge plate are clinched upon said rule section, the position of said hinge plate will be preserved accurate.

Manifestly, other variations than those mentioned may be resorted to, and parts and features may be omitted or used without others Within the scope of the appended claims.

Hence, having now fully described my invention, I claim:

1. The method of accurately setting a swivel hinge plate or the like in predetermined position upon a rule section or leg of a folding rule, said hinge plate having a plurality of projections upon one side thereof forming locating points adapted to engage in the material of the rule section upon which said hinge plate is to be mounted, which method consists in cutting free the opposite ends of said hinge plate in outwardly extending flat form to provide special guides with sides spaced apart in opposed pairs at said ends, guiding the hinge plate by moving the same in a direction substantially perpendicular to the general surface of said hinge plate toward the rule section and simultaneously sliding the special guides in flat alined condition upon the ends of said hinge plate along opposed spaced sides of stationary guides toward said rule section during movement of said hinge plate, and forcing said hinge plate into intimate contact with said rule section whi e preserving the accuracy of the position of said hinge plate against lateral displacement with respect to said rule section preparatory to securing said hinge plate thereon.

2. The method of accurately setting a swivel hinge plate in position upon a folding rule section or leg, said hinge plate being substantially fiat and having a plurality of projections spaced apart forming locating points, which method consists in simultaneously cutting free both ends of the hinge plate from sheet metal and simultaneously cutting at least one outwardly extending fiat guide portion upon each end with corresponding opposed sides, forcibly moving the hinge plate in a direction at substantially right angles to the surface thereof toward a rule section or leg upon which said hinge plate is to be mounted, positively guiding said hinge plate in movement toward said rule section or leg by continuous engagement with the sides corresponding stationary guide means of the said guide portions on said hinge plate, bringing said hinge plate into intimate contact with said rule section laterally during the guided movement thereof so that the locating points become embedded in the material of said rule section while preserving the position of said hinge plate against lateral movement or shift with respect to said rule section laterally, and removing said rule section with the hinge plate thereon while retaining said hinge plate in accurately placed position thereon preparatory to permanently securing said hinge plate in place upon the rule section.

3. The method according to claim 2, wherein a die is used with two oppositely disposed end cutting portions spaced apart and each end cutting portion having a pair of opposed guide portions extending through said die from a cutting zone to a supporting zone for supporting a substantially flat rule section, and wherein a corresponding substantially flat nosed punch is used for moving the hinge plate toward said rule section and bringing it into intimate contact therewith, said punch having corresponding cutting guide portions with pairs of opposed sides co-operating with the sides of the guide portions of the end cutting portions of said die to cut the guide portions upon the ends of said hinge plate.

4. The method of accurately locating a metal plate upon a stationary article, said plate having at least one locating point in the form of a projection upon one said side thereof, which method consists in cutting free both ends of the plate in fiat alined condition thereof from sheet metal and simultaneously cutting pairs of profiled guide portions upon said ends, forcibly moving said plate in substantially flat condition after being out free toward said stationary article and causing the locating point to become embedded in the material of said article while preserving the accuracy of the position of said plate against lateral displacement with respect to said stationary article preparatory to permanently securing said plate to said stationary article, and shifting said plate laterally with said article from the position in which the plate is applied thereto into another position for further operation upon said plate while retaining the plate in intimate contact with said article.

References Cited in the file of this patent UNITED STATES PATENTS 1,211,458 Leavens Jan. 9, 1917 1,506,535 Kotzich Aug. 26, 1924 1,963,306 Maynard June 19, 1934 2,120,711 Phillips June 4, 1938 2,208,819 Smith July 23, 1940 2,310,177 Horton Feb. 2, 1943 2,500,721 Van Dijk Mar. 14, 1950 2,610,390 Locke Sept. 16, 1952 

